1. Field of the Invention
The present invention relates to a cryogenic refrigerator that includes a scotch yoke mechanism.
2. Description of the Related Art
A Gifford McMahon (GM) refrigerator is known as a refrigerator generating cryogenic temperature. The GM refrigerator changes volume of an expansion space by reciprocating a displacer inside a cylinder. In response to this volume change, the expansion space is selectively connected to a discharge side or an intake side of a compressor, thereby expanding refrigerant gas in the expansion space. To reciprocate the displacer, a known scotch yoke mechanism in which rotational movement of a crank rotated by a motor is converted to reciprocating movement may be used.